Abstract
Introduction
Ceramic-on-ceramic couplings are an attractive alternative bearing surface to eliminate or reduce problems related to polyethylene wear debris. Past disappointing experiences with alumina-ceramic bearings have led to many improvements in the manufacture and the design of ceramic implants. The purpose of this study was to report the results of contemporary alumina-on-alumina total hip arthroplasties (THAs) with regard to wear, osteolysis, and fracture of the ceramic in patients with osteonecrosis of the femoral head.
Methods
Between February 1998 and October 2003, 365 patients (432 hips) with osteonecrosis of the femoral head underwent cementless total hip arthroplasty using contemporary alumina bearings. There were 243 men and 122 women who had a mean age at the time of index operation of 43 years (range, 18 to 65 years). They were evaluated clinically and radiographically at 5 to 10 years (average, 7 years). During the follow-up, special regards were addressed to wear, periprosthetic osteolysis and ceramic failure.
Results
The mean Harris hip score was 94 points at the latest follow-up evaluation. All of the prostheses had radiographic evidence of a bone ingrowth. No implant was loosened radiographically and no implant was revised. Ceramic wear was not detectable in 83 hips where differentiation of the femoral head from the cup was possible on radiographs. Periprosthetic osteolysis was observed in no hips. Fracture of the alumina femoral head occurred in 5 hips, and fracture of the alumina liner occurred in 5 hips using sandwich-type ceramic liners.
Conclusion
The results of contemporary alumina-on-alumina THAs with a metal-backed socket and a cementless stem were encouraging in young, active patients. We believe that these improved alumina-on-alumina bearing implants offer a promising option for younger active patients.
